No power to system on initial startup- new build

I recently completed the initial construction of a new PC build (except for the case which is 7-8 years old) and am having trouble with basic startup. When I turn on the power and press the start switch on the front of the computer one of the case fans moves slightly (for less than a second) and the keyboard light comes on (less than a second) then nothing else happens (no beeps, just nothing). The power supply fan does not even come on. WHen I pulled the power supply back out, jumped pins 15 and 16 of the 24 pin connector, I do get power registering to the 22 other pins at their specs and the fan for the power supply comes on like normal. When the power supply was pulled out I checked all the other connectors for power (4-pin and 6 pin) and they are all right for voltage. When I reconnect the power supply to the board along with all other processor, hard drive (single), and DVD RW drives connected, I also do not get any power to the 6-pin PCI, 4pin extra processor power pins, or Molex 4 pin power pins that tested normal when the power supply was not connected to the board. I also tested the start switch on the front of the computer for continuity when I press it and it does have continuity when pressed, then open circuit when I release it. Finally, I closed the case with the power supply attached as I read on some other posts that some cases have to be closed for the power to be on, and still the power does not come on.
Essentially, the power will work if unattached to the board and doesn't work when it is. Is this likely to be a startup switch problem or a board pin 15-16 problem? Thanks. DOug
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  1. Best answer
    Did you plug in the 8pin cpu power to the motherboard?
  2. Yes the 8 pin conector was connector was connected. I would note also as I am using an old case that none of the case fans attach to the mboard, they simply are powered by Molex connections. Could it be that the mboard won't work if the fans are not directly attached?
  3. What PSU are you using?
  4. Antec Earthwatt 430 watt with GA-H67A-UD3H-B3 mboard
  5. Best answer selected by sdlehmanntom.
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